Omron NT31 NT31C manual Data Format, Settings at the Bar Code Reader, About RS/CS Control

Connecting a Bar Code Reader Section 3-4

Settings at the Bar Code Reader

3-4-3 Data Format

Make the settings shown in the table below at the bar code reader. Make sure that the communications speed, parity, stop bit, and data bit settings match the communication settings made at the NT31/NT31C. For details on the setting method, refer to the instruction manual for the bar code reader used.

Item	Possible Settings
Communications speed	4800, 9600, 19200 bps
Parity	EVEN, ODD, NONE
Stop bits	1 or 2 bits
Data bits	7 or 8 bits
Preamble	STX
Postamble	ETX
RS/CS control	Available
Communication protocol	No-protocol mode
Transmission of number of bar code label digits	Transmission prohibited
Transmission of ID characters	Transmission prohibited
Bar code types	Multi-reading (all types can be
	read)
Trigger switch setting	Automatic reading mode

About RS/CS Control

During bar code reading, the NT31/NT31C performs RS/CS control. When the Input Method setting of the NT31/NT31C is set to Auto, the RS signal is turned OFF, prohibiting the next input, until the read data has been notified to the host.

Because of this, when the Auto setting is made, the next input is not possible until the data has been notified to the host.

However, when the setting is Auto and the RS/CS signals of the cable are shorted, RS/CS control is ineffective. Consequently, data input from the bar code reader to the NT31/NT31C is updated regardless of whether or not the data is notified to the host.

For details, refer to the instruction manual for the bar code reader used.

The data format for communication when using the bar code input function of the NT31/NT31C is shown below.

STX	Data	Data	Data	ETX
(02H)				(03H)

The characters which are effective as data are hexadecimal codes from 20 to 7FH, and the maximum data length is 40 bytes.

Data which does not follow the data format described above is invalidated and discarded.

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